Lewis & Short

armŏrăcĭa, ae, f. (armŏrăcĕa, Col. 6, 17, 8; Pall. 4, 9, 5; 11, 11, 4: armŏ-răcium, ii, n., Col. 12, 9 fin.), = ἀρμορακία, horseradish: Cochlearia armoracia, Linn.; Col. 9, 4, 5; 20, 4, 12; cf. Dioscor. 2, 138.